Disallow assignment to op results, including bit slices #698
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edwardcwang
approved these changes
Sep 27, 2017
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Assigning to the result of a bit slice now errors out in Chisel instead of propagating to FIRRTL.
A similar check is also performed for bulk-connect, but won't catch all cases as it is performed before sinks and sources are resolved.
Fix for #399. The error text isn't perfect (just says "Cannot reassign to read-only $this"), but at least you get a line number which should narrow down the issue. With a richer set of bindings (like a BitExtractBinding) it may be possible to generate a more specific error message (like "Cannot reassign to $this, bit extract results are read-only")